Smoke & Charcoal GrayFor quilts big or small, finishing is made simple with yards of continuous bias tape in shaded tonal hues. Charcoal Gray Marble Quilter's Bias Binding, 2 1/2" wide, pre-folded in half once, sold by the yard. To determine how much bias you will need, add the width and length of the quilt together, multiply by 2, and add at least 12" for turning corners and overlapping at the end.